The application generally relates to a control system and method. The application relates more specifically to a system and method for controlling a road cutting machine for cutting a series of depressions along surfaces of roadways.
As motor vehicle operators become fatigued or distracted, the possibility of the vehicle drifting off the road or over the center line and into the opposite lane of traffic increases, either of which can potentially lead to disastrous results. To minimize this occurrence, a series of depressions are cut along the shoulders or center line of the roadway, referred to as ground-in rumble strips. The purpose of the rumble strip is to alert drivers when they have drifted outside their traffic lane by creating a sound and causing vibration to their motor vehicle as its tires travel over the depressions.
In some prior art cutting machines, various methods are employed for engaging and disengaging the cutting drum into the road surface to cut the depression and for repositioning the cutting drum for the next cut. One method of raising and lowering the cutting drum requires an operator to manually control a hydraulic cylinder which is connected to the cutting drum. A problem with this method is that it is difficult for the operator to move the cylinder controls quickly enough to achieve a sufficient production rate (defined as forward feet per minute) while cycling the cutter.
In other prior art cutting machines, electronic controllers may be used to achieve better production rates. For example, U.S. Pat. No. 5,415,495, assigned to the assignee of the present invention, describes an electronic controller responsive to a signal indicative of the forward distance traveled by the cutter. The controller electronically controls an engaging device so that the cutting drum moves out of and into contact with the road surface in accordance with the distance that the cutting drum moves along the road surface and a specified dimensional profile of the depression, which are stored in the electronic controller. Controlling the cutting drum to meet the specified dimensional profile, however, requires further adjustments to the computer controller as the forward speed of the cutting machine increases. The operator must re-program the instruction parameters stored in the computer controller. Such re-programming of the instruction parameters is typically performed by connecting the computer controller to a laptop PC while the machine is idle. The operator is required to stop the machine from cutting in order to change program parameters, and the process for doing so causes a disruption to production and is time consuming.
As an alternative, potentiometers could be provided for the operator to make manual adjustments to the depth and hover parameters, i.e., the depth offset parameter of the cut and the hover offset parameter of the cutting head. Depth and hover offsets are voltage commands (e.g., 0 to 5 volt) that are added to or subtracted from a corresponding depth or hover parameter to adjust for cutting speed or field conditions, e.g., worn teeth on milling bits.
Intended advantages of the disclosed systems and/or methods satisfy one or more of these needs or provide other advantageous features. Other features and advantages will be made apparent from the present specification. The teachings disclosed extend to those embodiments that fall within the scope of the claims, regardless of whether they accomplish one or more of the aforementioned needs.